Tubular Glass Photobioreactors. Bringing Light to Algae

Transcription

1 Tubular Glass Photobioreactors Bringing Light to Algae

2 SCHOTT is an international technology group with more than 130 years of experience in the areas of specialty glasses and materials and advanced technologies. With our high-quality products and intelligent solutions, we contribute to our customers success and make SCHOTT part of everyone s life. With a production capacity of more than 140,000 tons and production sites in Europe, South America and Asia, SCHOTT s business segment Tubing is one of the world s leading manufacturers of glass tubes, rods and profiles. Approximately 60 glass types are produced in large external diameters and a variety of lengths based on site-overlapping strategies in development, production and quality assurance. SCHOTT Tubing provides customized products and services for international growth markets such as pharmaceuticals and electronics as well as industrial and environmental engineering. Title: PBR, located at A4F-Algae for Future, Portugal

3 Contents 4 Algae Production Systems 5 Crystal Clear Benefits Product Range Round Tubing DURAN Oval Tubing CONTURAX U- and J-Bends Manifolds Couplings Packaging 16 Borosilicate Glass Properties 18 Closed Tubular Photobioreactors versus Open Ponds 19 Borosilicate Glass versus Polymer Materials 20 Fluid Mechanical Properties 22 Complete Tubular Photobioreactors (PBRs) 23 Technical Terms of Supply 12 15

4 4 Algae Production Systems Common photosynthetic algae cultivation systems are either open ponds or closed photobioreactors (PBRs). Open ponds Open ponds are typically built in circular or race way configurations. The water is kept in motion, for example by paddle wheels. Open ponds are seemingly inexpensive and easy to build. However, poor light utilization, danger of contamination and high water evaporation are the main challenges, which lead to low biomass output per area and large water uptake. Some difficulties can be overcome by rooftops however this increases the costs further. Closed system Closed systems are dominated by tubular and flat-plate reactors. Other options are bags, coils or domes. Flat plate systems have received a lot of attention due to their large illuminated surface area, but the technology suffers from heating problems and a strong tendency to build up biofilm formations on the inner walls. Tubular systems on the other hand reduce these drawbacks while maintaining the advantages of optimal light input and high productivity. Therefore closed tubular glass Photobioreactors (PBRs) with long lifetimes and easy cleanability, are very well suited for the highly reproducible cultivation of algae resulting in the highest possible growth rates. As such, tubular glass PBRs are best suited to provide bio-security for high quality inoculum used in open ponds. Haematococcus pluvialis, green phase Haematococcus pluvialis, red phase

5 5 Crystal Clear Benefits of Closed Tubular Glass PBR Systems Bio-Secure protection against bio-contamination Productive highest biomass output per production volume Cost Efficient lowest total cost of ownership Durable lifetimes of 50 years and more Resistant high stability against UV, chemicals, scratches and corrosion Food Safe food and pharma grade

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7 7 Product Range Overview Helical System Fence System U-Bend or J-Bend Coupling Round or Oval Tubing Manifold

8 8 Product Range Borosilicate Glass Tubing DURAN Round tubes Item No. Joint Outside Diameter Joint Wall Thickness Tube Length Volume per tube Package Type* Package Content Number of Tubes Weight approx. kg mm in mm in m in l gal Carton Pallet Carton ± ± ± ± Pallet Wooden Box Pallet Carton Pallet Carton ± ± ± ± Pallet Wooden Box Pallet Carton ± ± ± ± 0.03 Pallet Pallet Weight approx. lb Other dimensions upon request. * for explanation regarding package type please see page 14

9 10 Product Range Borosilicate Glass U- and J-Bends DURAN Helical System Tube U-Bend Item No. Joint Outside Diameter Joint Wall Thickness Joint Bend Width Approx. Bend Height Straight Side Length Volume per Bend (approx.) Package Type Package Content mm in mm in mm in mm in mm in l gal Number of Tubes ± ± ± ± ± ± > 45 > ± ± ± ± ± ± > 45 > Carton 34 Pallet 544 Carton 21 Pallet 189 Bend Types are used for the following applications U-Bend: for gaps between tubes of 65 mm/2.56 in or more J-Bend: for smaller gaps as of 40 mm/1.57 (couplings are shifted in every second row) U-Bend long: are used in combination with J-Bends and U-Bends

10 11 Tube U-Bend long Item No. Joint Outside Diameter Joint Wall Thickness Joint U-Bend Width Approx. U-Bend Height Straight Side Length Volume per Bend (approx.) Package Type Package Conetent mm in mm in mm in mm in mm in l gal Number of Tubes ± ± ± ± ± ± > 145 > Carton 21 Pallet 189 Tube J-Bend Item No. Joint Outside Diameter Joint Wall Thickness Joint U-Bend Width Approx. U-Bend Height Straight Side Length Volume short leg long leg per Bend (approx.) Package Type Package Content mm in mm in mm in mm in mm in mm in l gal Number of Tubes ± ± ± ± ± ± > 45 > 1.77 > 145 > Carton 21 Pallet 189 U-Bend U-Bend long J-Bend

11 12 Product Range Couplings Item No. Outside Diameter Tube on Side 1 Outside Diameter Tube on Side 2 Package Description Package mm in mm in Number of Couplings Weight approx. kg Weight approx. lb Bag Standard (1) Pallet Standard Bag Standard Pallet Standard Bag Standard Slim (2) Pallet Standard Slim (2) Bag Standard Slim (2) Pallet Standard Slim (2) Open Standard Coupling Toolbox 54 with torque wrench for closing of coupling and tools for opening Toolbox 65 with torque wrench for closing of coupling and tools for opening Open Standard Slim Coupling

12 13 Additional Equipment Item No. Outside Diameter Tube on Side 1 Outside Diameter Tube on Side 2 Package Description Package mm in mm in Number of Couplings Weight approx. kg Carton Maintenance kit (no partition wall) (3) Carton Maintenance kit (no partition wall) Carton Adapter (4) Weight approx. lb Specially developed for tubular photobioreactors: The couplings are designed for SCHOTT glass tubes with plain tube ends according to the product range shown in this brochure. Successfully tested for 10 years lifetime regarding - 3 bar pressure resistance - UV-resistance - Regular cleaning cycles with various chemicals Fast installation allowing for reduced built up time of the reactor Easy to disassemble and re-use allowing for fast modification or extension of a reactor system Easy handling with pre-assembled devices and a special tool kit including a torque wrench (1) Standard With partition wall to assure glass separation and smooth transition (2) Standard Slim (3) Maintenance Allows easy exchange of tubes, no partition wall (4) Adapter Allows connection to pheriphery tubes with 2.5 inch outer dimension

13 14 Product Range Borosilicate Glass Manifolds DURAN Fence System Manifolds are placed at the ends of tubular PBR fences and function as U-Bends and in- and outlets. Bio secure and food safe full glass solution Available with closed ends or with flange Outside diameter of arms: 54 mm/2.13 in or 65 mm/2.56 in for use with standard couplings Number of arms, distance between arms, total length etc. are customized with a minimum order quantity of 25 pieces Manifold with closed end Manifold equipped with a flange

14 15 Packaging Cartons Tubes, up to 2.5 m length, low quantities U-Bends Couplings Manifolds Light management products Pallets Tubes, any size, medium and large quantities Wooden boxes Tubes, 4 m length or larger Packaging with cartons Packaging with pallets Packaging with wooden boxes

15 16 Borosilicate Glass Properties Metric US Chemical Composition Coefficient of mean linear thermal expansion α acc. to DIN ISO K -1 (20 C; 300 C) K -1 (68 F; 572 F) SiO 2 B 2 O 3 Na 2 O + K 2 O Al 2 O 3 Transformation temperature T g 525 C 977 F Density ρ at 25 C 2.23 g cm lb ft -3 main components in approx. weight % Modulus of elasticity E (Young s modulus) N mm lb in -2 (psi) Chemical Resistance Poisson s ratio μ Hydrolytic Class (DIN ISO 719) HGB 1 Thermal conductivity λ w at 90 C 1.2 W m -1 K Btu hr -1 ft -1 F -1 Acid Class (DIN 12116) Class S 1 Refractive index (λ = nm) n d Alkali Class (DIN ISO 695) Class A 2 Stress-optical coefficient (DIN ) K mm 2 N mm 2 N -1

16 17 Transmission Pressure Resistance of Tubing made of Borosilicate Glass The following formulas apply to stress free, pristine tubing and cylindrical hollow bodies with a circular profile, uniform wall thickness with open ends, free from thermal load, under internal positive pressure and external negative pressure. Estimation of the maximum pressure resistance (p) p = WT 140 bar OD WT Estimation of the minimum wall thickness (WT) ,000 1,200 Wavelength [nm] Transmission [%] (left scale) Solar irradiation [W. m -2. nm -1 ] (right scale) 0 WT = OD p 140 bar + p OD = Outside Diameter in mm WT = Wall Thickness in mm p = Pressure Resistance in bar Note When the glass tube is filled with water, the transmission increases from about 92% to 95.6% due to reduced reflection losses at the inner glass/water interface. K S = 70 bar permissible load referring to standard DIN EN 1595: Pressure Equipment made from Borosilicate Glass 3.3 General Rules for Design, Manufacture and Testing Other points to be considered: AD 2000-leaflet N 4, edition : Pressure vessels made of glass, with encl. 1, edition : Evaluation of faults in walls of glass pressure containers AD 2000-leaflet B 1, edition : Cylindrical and spherical shells under internal pressure overload According to DIN EN 1595 Pressure Equipment made from Borosilicate Glass 3.3 General Rules for Design, Manufacture and Testing, DURAN is an approved material and may be used for the construction of pressure equipment.

17 18 Features and Benefits of Closed Tubular Photobioreactors versus Open Ponds Contamination Very low risk of contamination compared to open ponds, where other microorganisms or insects have easy access No limitation regarding the algae species that can be grown, in part due to effective blocking against competing organisms Productivity Significantly higher productivity in terms of mass per area and day Enhanced use of land Algae concentration at harvest Notably higher concentration in terms of mass per liter More efficient harvesting procedure Water loss No evaporation within closed system compared to open ponds, which can lose significant water amounts, resulting in salt precipitation hazard Water loss is limited to external factors, such as cooling processes, use of green houses, tube diameter, target temperature etc. Closed tubular photobioreactor Biomass quality Biomass quality is highly reproducible due to excellent process control of tubular PBR systems High value products or high quality inoculum can be produced with optimum reliability Production flexibility Easy cleanability allowing for defined initial status any time, thus switching algae species is possible and secure Use of GMO* for improved production process GMO production is possible with closed reactor design * GMO = Genetically Modified Organism Open pond

18 19 Features and Benefits of Borosilicate Glass versus Polymer Materials Light transmission Fire protection Leaching Cleaning Thermal stability Cost saving Sagging Excellent light transmission (see page 17 for details) No solarization or browning effect No UV-protective additive or coating necessary to secure material properties Lifetime of Borosilicate glass tubing > 50 years Glass does not burn or give off toxic fumes Glass is a chemically highly resistant material. With plastic tubing, depending on the polymer type, monomers or oligomers of hazardous substances such as Bisphenol-molecules can be leached into the algae culture. Mechanical stability allows continuous in-line cleaning with polymer pellets Chemical stability allows cleaning in place (CIP) Lower material and maintenance costs compared to quality polymer tubes No need for expansion loops due to low thermal expansion Example: for 5.5 m long tubes and a temperature increase of 20 C/36 F the expansion of Borosilicate glass is only 0.36 mm/0.01 while polymers expand from mm/ depending on polymer type Glass tubes can last fifty years and longer Reduced number of racks due to high mechanical stability, which allows increased tube support distances without sagging of tubes Example: double distance compared to PMMA (for details see below) Reduced number of connections due to long tube lengths of 5.5 m No permanent deformation of glass tubes in contrast to polymer tubes Borosilicate glass Polymer Sag [mm] Position along tube [m] Glass Tube PMMA Tube Sagging of water filled tubes (outer diameter 65 mm, wall thickness 2.2 mm, length 2.75 m). The sag of the glass and polymer tubes is 0.5 mm and 8.6 mm, respectively. The polymer tube would need to be supported every 1.5 m for the same sag as the glass tube.

19 20 Fluid Mechanical Properties For the construction of a tubular photobioreactor the expected pressure loss in the system and other fluidmechanical properties can be simulated numerically for a given tube geometry, velocity and temperature. This allows an optimal pump design. In the following, the impact of the components with an outer diameter OD of 65 mm and a wall thickness of 2.2 mm for the tubes and 2.8 mm for the U-Bend is shown. The velocity of the algae culture in the round tube or oval section corresponds to the value u p = 0.7 m/s ( Q = m³/s) and the density to ρ = 993 kg/m³. For u p = 0.7 m/s Q in 10-3 m 3 /s Δ p v in Pa ζ Round Tube (L = 5.5 m) Oval Tube (L = 5.5 m) U-Bend Steel Tube ( L = 5.5 m) k = 0.2 mm k = 0.02 mm Pressure loss Δ p v = ζ 8ρ Δ p Q 2 v : Pressure loss in Pa d 4 π 2 ζ : Pressure loss number ρ: Density in kg/m 3 u p : Process velocity in m/s d: Inner tube diameter in m Q: Volume flow rate m 3 /s d round tube: Q = 2 π u 4 p d oval tube: Q = 2 π 0.82 u 4 p Dean-vortex appearance in an U-Bend computer simulation (ANSYS CFX )

20 21 The pressure loss numbers ζ for the U-Bends and oval tubes change slightly with the volume flow rate Q. As the flow elements are arranged in series, each component contribute as an additive element to the global pressure loss Δp v-ε of the reactor. The U-Bends of SCHOTT show small values for ζ compared to literature indicating a smoother flow guidance and thus a low contribution on the total required electrical power of the photobioreactor. Electrical Power Δ p v-ε Q P el = η p P el : Electrical power Δ p v-ε : Sum of pressure loss in Pa Q: Volume flow rate in m 3 /s η p : Pump efficiency at operating point (η p < 1) Pressure loss number: U-Bend (OD 65 mm, WT 2.8 mm) Pressure loss number: Tubes (OD 65 mm, WT 2.2 mm, L=5.5 m) ζ [-] ζ [-] Volume flow rate Q [10-3 m 3 /s] Volume flow rate Q [10-3 m 3 /s] Oval tube Round tube Steel tube (k=0.2) The investigated oval tubes of SCHOTT with their elevated light absorption need only electrical power compared to the one of conventional round tubes with the same process velocity. Thus a higher productivity of the photobioreactor can be achieved at similar move to next line so there are no operational energy costs. Research done in cooperation with: Institute of Fluid Dynamics, LSTM, Technical Faculty, University Erlangen-Nuremberg, Germany

21 22 References - Complete Tubular Photobioreactors SCHOTT has formed alliances and partnerships all over the world. This allows us to provide complete tubular photobioreactors according to your needs. Please contact us for further details. Photo courtesy of Heliae Inc., USA Photo courtesy of Varicon Aqua Solutions Ltd, UK Photo courtesy of A4F-Algae for Future, Portugal Photo courtesy of Algatechnologies Ltd, Israel

22 23 Technical Terms of Supply Detailed information on permissible faults, definition of faults, testing methods and testing units are available upon request. Reduced tolerances are also available upon request. Regarding quality issues the relevant Technical Terms of Supply for the application apply to all sales and are binding unless separate written agreements with respect to specification have been agreed upon. SCHOTT and CONTURAX are registered trademarks of SCHOTT. DURAN is a registered trademark of the Duran Group GmbH. We thank our customers and partners for their kind assistence in providing product samples and photos. SCHOTT declines any liability with respect to the correctness or completeness of any information or data that is expressly or implicitly contained in this brochure.

23 Tubing SCHOTT AG Erich-Schott-Strasse Mitterteich Germany Phone +49 (0)9633/80-0 Fax +49 (0)9633/ Agb KR / Printed in Germany